//// image replacement ////

// set variables
var imgOn = '';
var imgDir = 'images/';
var imgOver = '-over';
/* cache images - listed as arguments in the function call */

//	 returns an image cache object
function imgCache() {
	this.onImgs = new Array(arguments.length);
	this.offImgs = new Array(arguments.length);
	for (i = 0; i < arguments.length; i++) {
		onImgs[arguments[i]] = new Image();
		offImgs[arguments[i]] = new Image();
		onImgs[arguments[i]].src = imgDir + arguments[i] + imgOver + '.gif';
		offImgs[arguments[i]].src = imgDir + arguments[i] + imgOn + '.gif';
	}
	return this;
}

// generic image rollover function
function imgChange(imgName, state) {
	if (state == 'on'){
		document[imgName].src = onImgs[imgName].src;
	}
	else {
		document[imgName].src = offImgs[imgName].src;
	}
}

// generic image rollover function
function imgFormChange(elementName, state) {
	var elemNam = elementName;
	var x = document.getElementById(elemNam);
	if (state == 'on'){
		x.src = onImgs[elementName].src;
	}
	else {
		x.src = offImgs[elementName].src;
	}
}